# IsJSON

Evaluates whether a string is in valid JSON (JavaScript Object Notation) data interchange format.

## Method Signature

```
IsJSON(var=[any])
```

### Arguments

| Argument | Type  | Required | Description                | Default |
| -------- | ----- | -------- | -------------------------- | ------- |
| `var`    | `any` | `true`   | The value to test for JSON |         |

## Examples

### isJSON Example

Returns true when the argument is a valid JSON value.

[Run Example](https://try.boxlang.io/?code=eJzLLPYK9vfTUFCKNtQx0jGOVVLQtOYCAD3kBNc%3D)

```java
isJSON( "[1,2,3]" );

```

Result: true

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJydj7FqwzAQhmf7KQ5NDmionBYKxUOTThlSirsFD6f0aASy3ZytGvfpKzkppK49NCAh8Yvv%2B08dm5aeXPmRgEVNNhOPzNgLCZ%2FImWk2TV0lIHZKpnJZCFjA4iHu%2FkC5qd4tQeVKTexR62ikULNoyx6eZETjGqPS5e3dfPEFDZ1pD9AQG7Tmizb583YkDFH%2B8372D%2Bpp%2BaquLWF1pb1lD82610zoI79fTfl%2F%2BW88gfRG3UtQl%2BvUHdqP3EMGR0fcb6nz%2F0ZEqbX2FcJ37A%2FIQ1m4%2BGwXR35FAoUMhxZxVMhztj9lbyGLi%2BmvvYSi0fhhhGGWb41ZwUw%3D)

```java
writeDump( label="Array", var=isJson( "[1,2,3]" ) );
writeDump( label="Single number value", var=isJson( 1 ) );
writeDump( label="String value", var=isJson( "susi12345" ) );
writeDump( label="String value with serializeJSON", var=isJson( JSONSerialize( "susi" ) ) );
writeDump( label="Boolean value with serializeJSON", var=isJson( JSONSerialize( true ) ) );
writeDump( label="CreateDateTime with serializeJSON", var=isJson( JSONSerialize( CreateDateTime( 2018, 1, 1, 1, 1, 1 ) ) ) );
qry = queryNew( "aaa,bbb", "varchar, varchar", [
	[
		"a",
		"b"
	],
	[
		"c",
		"d"
	]
] );
writeDump( label="Query", var=isJson( qry ) );

```

## Related

* [ArrayIsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/arrayisempty)
* [arrayIsEmpty](https://github.com/ortus-boxlang/boxlang-docs/blob/v1.x/boxlang-language/reference/built-in-functions/decision/arrayIsEmpty.md)
* [Attempt](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/attempt)
* [IsArray](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isarray)
* [IsBinary](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isbinary)
* [IsBoolean](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isboolean)
* [IsClosure](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isclosure)
* [IsCustomFunction](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/iscustomfunction)
* [IsDate](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdate)
* [IsDateObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdateobject)
* [IsDebugMode](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdebugmode)
* [IsDefined](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdefined)
* [IsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isempty)
* [IsFileObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isfileobject)
* [IsIPv6](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isipv6)
* [IsLeapYear](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isleapyear)
* [IsLocalHost](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/islocalhost)
* [IsNull](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnull)
* [IsNumeric](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnumeric)
* [IsNumericDate](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnumericdate)
* [IsObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isobject)
* [IsQuery](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isquery)
* [IsSimpleValue](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/issimplevalue)
* [IsStruct](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isstruct)
* [IsValid](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isvalid)
* [IsXML](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxml)
* [IsXmlAttribute](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlattribute)
* [IsXMLDoc](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmldoc)
* [IsXMLElem](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlelem)
* [IsXMLNode](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlnode)
* [IsXMLRoot](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlroot)
* [LSIsNumeric](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/lsisnumeric)
* [structIsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/structisempty)